B/W 702 s3

What do you mean by "average"?

Can you be more specific?

My B&W 803 D3 needed lots of changes to speaker and listening seat position, and also two subwoofers, before they sounded the way I wanted them to.

I have the 703S3 and I went through a few amps before I liked the sound of them.   I agree with you they sounded “ok”.   One day my buddy brought his Macintosh amp and they sounded totally different.   I ended up going with a Passlabs x150.8 and they sound awesome.   B/w speakers need really powerful amps to sound good.   Powerful I mean high current.   Don’t think the Rotel is doing it for you.  I later added two Rel subs and they sounded even better.   Having said that the pass labs had them plenty of bass.  They subs just increased the sound stage. 

I had a similar experience with my Martin Logan 20i - they sounded just "okay" and no "punch".  So, I've decided to sell them - and moved them into a small room and temporarily connected to a vintage Pioneer SA-9800 (100 WPC).  It was like I got an upgrade to a much better pair of speakers, and I actually still have them to this day. 

In summary - I would say a more powerful amp and some full-er range speakers should solve all the issues - and we only live once.

Having owned a Rotel amp and being familiar with the B&W signature sound, there may be a synergy issue. My Rotel tended to be on the bright side and most of the B&W's I've listened to seem to be a bit bright as well. Some of the others who posted suggested a sub and I also think that will help. Despite being a bit bright, B&W's are also very revealing and provide excellent soundstages and detail. If I was to switch anything out, it would be the amp. 

I have a pair of Fyne F-72s with 8" woofers, and they were lacking in punch at the low end.  Still are, but I added two Rythmik FS12e subs, and that made a HUGE difference in the sound, even beyond the lower bass register; it was a definite transformation.  I am not familiar with the Rotel line, but I am driving my Fynes with two Odyssey Kismet mono blocs--which I will soon have converted to stereo to vertically bi-amp the speakers, and the sound quality is superb ... again, with the two subs.